1. Infectious Disease Notes

2. What is disease?
A disease is any change, besides an injury that affects the normal functioning of the body.

3. What is an infectious disease?
An infectious disease is any disease that can be transmitted from one person to another person.

4. What is a pathogen? A pathogen is any agent that can cause disease.
In humans, pathogens fall in six categories.
Bacteria
Viruses
Protists
Worms
Fungi
Prions

5. What is a bacteria?
Bacteria are single-celled organisms that are prokaryotic.
Prokaryotic means ‘without a nucleus’
Most bacteria do not harm humans.
Many bacteria are helpful to humans such as the bacteria in the intestinal tract.
Some bacteria cause infections.

6. What is bacteria? .
Antibiotics kill bacteria in a wide variety of ways.
It is very important to finish all antibiotics as prescribed by your doctor.

8. What are some dieases caused by bacteria?
Most infected cuts and scrapes
Urinary tract infection
Strep throat
Diptheria
Pneumonia

9. What is a virus?
A virus is a small infectious agent that can only reproduce inside of living things.
Not alive, but can reproduce inside of living things.
Viruses cannot be killed by antibiotics.
Viruses are killed by antiviral medications; currently, we do not have many antiviral medications.

10. What are some viral diseases?
Common cold
Stomach flu
Influenza
Chickenpox
Measles
Smallpox
Polio

11. What is a protist?
Protists are one-celled organisms that have a nucleus.
Common source of infections from drinking contaminated water.
In Michigan, Giardia lamblia causes diarrhea in campers who drink ground water.
Malaria is caused by a protist

12. What is a worm? People can be infected by flatworms and roundworms.
Tapeworms attach to the digestive system of humans and cause severe malnourishment.
Hookworms do the same thing as tapeworms.

13. What is a fungi?
Fungi are multicellular organisms with a cell wall that do not use photosynthesis.
Fungi do not cause many diseases in humans, but can be very difficult to treat when infections occur.
Yeast infections (including thrush)
Athlete’s foot
Jock itch

14. What is a prion?
A prion is a protein that is folded incorrectly and causes proteins nearby to fold incorrectly.
This can eventually kill the cell.
Very, very rare
Mad cow disease
Cruetzfield-Jakob disease